Flying through St. Louis will become more expensive if Trans World Airlines ceases to exist, some industry analysts warn.

American-TWA

Analysts say possible effects of a merger could include:

Higher business fares. Some estimate a single-digit percentage increase on TWA routes.

No more consolidator fares. The pulling of TWAs fares from online airline consolidators.

Higher corporate rates. Elimination of some deep discounts offered to corporations that frequently use TWA.

For years, travelers flying to Lambert-St. Louis International Airport or making connections there have found some good deals.

Financially ailing TWA, which agreed to be bought by American Airlines last week, often offers attractive fares on coast-to-coast flights through its St. Louis hub. The airline, which operates three flights a day to Honolulu, Maui and Kona, also offers deeply discounted fares through airline consolidators such as Lowestfare.com.

Another reason St. Louis stands out for low fares is that its No. 2 carrier, discounter Southwest Airlines, serves 21 destinations from there.

A November survey of airfares by the American Express Business Travel Monitor shows that business fares from Lambert were about 32 percent below the U.S. average. But if American Airlines proposed takeover of the airline comes to pass, fares will rise, airline experts say.

"Were not talking about St. Louis becoming a place only for the rich and famous," says airline consultant Michael Boyd of Evergreen, Colo. "But youll find fares edge up. ... Theyve been below economic levels."

Bestfares.com editor Tom Parsons says he expects American to cut 25 percent to 30 percent of flights out of St. Louis to make more money on fewer flights. American has said it intends to increase service at St. Louis.

Together, American and TWA control 900,000 available seats, or about 16 percent of the market, between the U.S. Mainland Hawaii.

What might be ahead?

Higher business fares: Analysts say American Airlines will increase TWAs fares to help bring the St. Louis operation to profitability. Boyd predicts a single-digit percentage increase on TWA routes if the buyout is approved.

Fares are expected to rise most steeply on routes that American and TWA dominate, such as St. Louis-Dallas/Fort Worth and St. Louis-Chicago.

"Business fares will creep up a little faster and higher as competition starts to slim out," says Thom Nulty, president of Navigant International, a travel management company in Denver.

Parsons says business travelers will also miss TWAs FirstUp fares, which are full coach fares that permit upgrades to first class if seats are available. Travelers must connect through St. Louis or fly nonstop from New Yorks JFK.

No more consolidator fares: American Airlines is likely to pull TWAs fares from airline consolidators, analysts say. Travelers can buy discounted TWA tickets on consolidators, such as Cheap Tickets of Honolulu.

TWA bargains found on former TWA Chairman Carl Icahns discount outlet, Lowestfare.com, may not be available if American buys the airline. American officials have indicated they will not honor TWAs contract giving Icahn access to inexpensive TWA tickets.

For example, round-trip TWA fares between Seattle and Miami, with a Saturday night stay and 21-day-advance purchase, were $271 on Travelocity.com, $261 on Cheaptickets.com and $205.65 on Lowestfare.com when USA Today checked.

Higher corporate rates: TWA offers deep discounts to corporations that frequently use the airline. But if the merger is approved, American may not offer the same discounts. State Farm of Bloomington, Ill., says many of its 80,000 employees fly on fares negotiated with TWA.

"We still dont know how its all going to shake out," says State Farm spokeswoman Ana Compain-Romero. "It could have a big positive or negative effect on us."